def none_repeating(nums):
    for num1 in nums:
        nums1 = nums.copy()
        nums1.remove(num1)
        for num2 in nums1:
            nums2 = nums1.copy()
            nums2.remove(num2)
            for num3 in nums2:
                print(str(num1) + str(num2) + str(num3), end=' ')
        print()


if __name__ == '__main__':
    none_repeating([1, 2, 3, 4])
